Sideloading is the installation of an application on a mobile device without using the device’s official application-distribution method.
Sideloading works differently on different mobile platforms. To enable sideloading on an Android OS device, for example, the end user simply checks a box in the operating system settings. On an Apple iOS device, however, the end user must jailbreak the device to enable sideloading. Once sideloading is enabled, the user can download and install applications from any website or third-party app store.
Sideloading offers mobile device users a way to access more applications than are available through commercial app stores such as Google Play or the Apple App Store, but it is important for the end user to understand that sideloading a third-party app can pose risks. Commercial app stores screen for malware and other threats and assume responsibility for digital rights management (DRM). Third-party apps may not have been screened for malware and may be pirated.